A compressor impeller, represented by a compressor impeller for a turbocharger for instance, is conventionally manufactured by placing a workpiece having a shape of a cone or a truncated cone on a supporting pedestal and then cutting the lateral face of the workpiece with a machine tool or the like while the center portion of the workpiece is being pressed in the axial direction to be fixed on the supporting pedestal by a fixing device provided on the opposite side of the supporting pedestal or by a female screw which corresponds to a male screw provided through the impeller. Patent Document 1, for instance, discloses an invention related to a machine tool for machining a compressor impeller for a turbocharger as a conventional technique related to the prevent disclosure.